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How is the effect of wind on arrival time handled?
If a commercial plane encounters strong tailwinds, would the pilots set the autopilot for a fixed arrival time (if that is possible), or would it be ok to arrive way ahead of schedule?
I imagine this could disturb airport operations, and that there are fuel economy considerations: if I was the airline, I would try to minimize fuel consumption.
But if I were ATC, random arrival times could cause chaos. Passengers in turn would probably be happy to arrive as fast as possible. It seems like there are conflicting interests.

As a side comment, all eastbound flights over the Atlantic have strong tailwinds (jet streams).

Above the continental US too, no? I was recently on a Dulles - SFO flight which got 200 mph headwinds on the first half the flight - then 50 mph tailwinds over Utah, Nevada and the Sierras to California.

For the Atlantic, it is quite noticeable indeed, as eastbound flights reach Europe in about 9 hours whereas westbound flights from Europe take 11 hours to reach the US (roughly).

Yes over US, either the polar jet stream or the subtropical one. See this news for example. You may want to ask a new question about the practical effect of the jet streams over lands.

@mins A jetstream is a unique phenomenon that resides at the tropopause at frontal boundaries, into the upper corner of the warm air mass, where there is a kind of watermelon seed through your fingers effect that makes a fairly narrow little river of air flow at high speed.  Flights may be able to get into a jet or may not, but what you're really describing is pressure pattern flow and prevailing winds which generally favour west to east. When the eastbound North Atlantic Tracks are set up each morning, the track system is shifted north to south to take best advantage of the pressure patterns.

@JohnK: I'm not sure I follow you.Jet streams exist at each side of the Ferrel cell in the Northern hemisphere. Better than words, this map of the current winds at 250 hPa (which is a fair approximation of the tropopause pressure). You can see winds of near 200 km/h over the US for example (at the time I post this message). You can use the menu (click "Earth" word) to see how this evolves in time.

@JohnK - I'm curious about "setting up the North Atlantic Tracks" every morning. Who does that? Is it the FAA? Each airline independently?

Frank:About the track system: Where to download NATs (North Atlantic Tracks) information?

@mins this is what I mean https://www.weather.gov/jetstream/jet  the jet forms in the upper corner of the cell.  The actual track is usually along a frontal boundary that is at the intermix zone of adjacent cells.

It will depend on constraints at the arrival airport. If there are no constraints, they will choose a speed that minimizes fuel burn, and arrive early if that's how it works out.
It's possible that the arrival airport may have constraints on arrival volume. As you pointed out, for busier areas, if aircraft arrive earlier than expected, it could cause things to get backed up. In that case ATC may have an aircraft adjust their speed or enter a hold in order to delay their arrival until capacity allows. Slowing down early is more efficient than arriving too soon and having to fly a holding pattern.
In areas without radar coverage, such as oceanic crossings, aircraft may be required to hold a certain airspeed in order to maintain separation from aircraft ahead and behind. In this case a pilot may not have much choice until they exit the oceanic airspace, and any adjustments would have to be made after that point.
ATC will do their best to ensure the safe and expeditious flow of traffic, but safety has to come first. While a pilot can choose to not follow ATC instructions in the case of an emergency, and in the interest of safety pilots have some amount of discretion in declaring emergencies as they see necessary, doing so just to reduce cost or for convenience would not be acceptable and may attract some scrutiny.
It's also possible that there would be constraints on the ground at the arrival airport. If the aircraft is scheduled to arrive at a certain gate at a certain time, and it arrives early, there may be another aircraft still occupying the gate, or support staff may not be ready to receive the aircraft. This would require the pilots to coordinate with the airline. If alternate arrangements can't be made, the airline might actually prefer the aircraft to be not arrive early. They would probably prefer to sit on the ground, with the engines off if possible, as that burns much less fuel than doing the waiting in the air.

In some cases atc has other options. Not trying to promote my own question, but see ymb1’s answer to https://aviation.stackexchange.com/q/29808/8730

It depends...  If I was a miles per gallon tightwad and was flight planning for a certain mach # in order to get there in a certain time, and found myself in a high altitude jet stream with a crazy tailwind, I might decide to slow down closer to the "min drag" speed of my plane to improve the air miles per gallon, knowing I can still arrive at the planned time.  Otherwise, I would just take the early arrival as a bonus.
However, if I'm heading for a saturated-traffic airport like Chicago, and an unexpected tailwind is going to make me arrive 20 minutes before the arrival time expected by ATC from the flight plan filed (and where I may have a reservation time slot assigned), and that arrival is going to add too much to the incoming crowd, ATC will probably put me in a hold to delay my arrival, which I won't have any choice about unless I request a fuel-state priority or declare an emergency.
One thing you can be certain of is that the airline itself will not on its own accord do anything to increase its fuel burn just to avoid arriving early; only if ATC forces it to.  Better to be on the ground sitting on the ramp, with one engine shut down and one idling, as you sit for 15 minutes waiting for the gate you arrived early at to become free.

Given a strong tailwind and freedom by ATC, most pilots will aim for the most fuel efficient power setting, to reduce costs; they are part of a business after all.

Is it ok to arrive with fuel tanks half full? Is the fuel kept in the tanks in that case? Years ago, I heard planes had to dump fuel before landing for safety reasons.

While a plane can be overweight, and need to dump fuel, this is more typically a problem when a plane prepped for a long flight has to make an emergency landing much sooner than planned.   It would be truly exceptional for a tailwind to be soooo strong that the plane would be overweight after a scheduled, planned route.   (Remember, the pilots know the wind forecast before they take off, so they know if they'll have a tailwind and approximately how strong it will be.)

Airplanes have a max landing weight, but usually a couple hours of flying is enough to get below it.  Lots of airliners don't have fuel dumping systems so if the airplane is above MLW they have to stooge around to burn it off, or if it's an emergency they'll land overweight, which requires the airline to do a special landing gear inspection.


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How do engines cope with various intake airflow speeds?
On a recent trip out of Washington Dulles to San Francisco, our B777 met with 200+ mph headwinds (as per the passenger entertainment system) at 35,000 ft for the first half of the route, before enjoying 50 mph tailwinds at 38,000 ft over Utah, Nevada and finally California.
The ground speed was displayed at 400 mph for the first half of the trip, then closer to 550 mph. Does that mean that air was rammed into the engines first at 400+200 = 600 mph, then in the second half of the trip at only 550 - 50 = 500 mph?
How do the engines cope with various intake airflow speeds?

These are two good questions, however the format of this site works best when only one question is asked at a time. I suggest you remove the second question from here and ask it again separately. Not only will you get a better answer, but it will be easier for future visitors to find their specific question.

@Ben - you are right. Let me work on that.

While the change you point out is not sensed by the engine, there is a more significant change actually sensed by the engine between takeoff (full thrust required at low airspeed), cruise (reduced thrust at maximum airspeed), end of descent (idle at reduced airspeed).

The airplane isn't aware of the winds. It just moves through the air mass at a certain speed, and if the air mass is moving it adds or subtracts from the aircraft's speed over the earth.
Drive your boat along a river with a 10 mph current upstream, then downstream, both at 25 mph on the boat's speedo.  The whole time your boat's showing 25 and the hydrodynamic forces acting on the hull are 25 mph forces. What's your speed relative to the shoreline going upstream compared to going downstream?  15 going upstream and 35 going downstream right?
Exact same thing with airplanes.  Navigating ships allowing for ocean currents is exactly the same as navigating airplanes in "air currents", they have "tailwind" currents and "headwind" currents and cross currents where you have to aim for point X to actually proceed to point Y, except things are happening in slow motion in the ship.

John - the question is more specifically about how/how much a jet engine can deal with varying intake airflow speeds. There is also a separate question about how the wind factors into trip planning.

I think John answered the first question very well... the question was specifically, "does a 200mph headwind and a 400mph GS mean that air was rammed into the engines at 600mph?"  Explaining the differences between GS and Air Speed, using a river analogy, is perfectly on-point.  There are still 2 unanswered questions: how do engines deal with varying intake airflow speeds (kind of nullified because the premise of the question is that there were varying intake speeds, which there weren't); and, do airliners adjust their AP to delay potentially early arrivals to avoid disrupting airport ops.

@John K - I move the second part of the question, about arrival times, to a separate question, as per Ben's comment.

@Jimmy - nullified? I thought that depending on the wind conditions, for a given ground speed, the air would flow into the engines at different speeds. Is it not the case? I was thinking that when designing jet engines, you would have to allow a range of intake speeds.

No the intake speed is the airplane's airspeed so it has to cope with the airplane's speed range, not wind effects.  Same as the water intake speed of a jet boat's impeller is the speed of the boat on the water, not the speed of the boat plus or minus the speed of the current.  The only time the wind effects engines is on some engines there are special procedures or setting thrust when on the ground in a crosswind or tailwind.  That's on the ground, where the air is coming from the side or behind.

At an altitude of 35000 feet, 600 mph works out to about Mach 0.904.
(There's a handy calculator for this here: https://www.grc.nasa.gov/www/k-12/rocket/machu.html.)
A Boeing 777 can fly at least as fast as Mach 0.89 at cruising altitudes. (Source: https://www.flightglobal.com/news/articles/flight-test-boeing-777-300er-fast-and-heavy-176585/.) It's possible you actually were flying at Mach 0.89 and the "600 mph" includes some rounding up.
Of course the aircraft is designed to fly slower as well. Otherwise you couldn't take off or land.
So yes, the engines are designed to deal with getting a lot of air in their intakes, up to some maximum amount, and also to operate while getting a lot less air.
When you drive a conventional automobile it also is able to operate on much less air than the maximum it can take.
The Mach number on the second part of the trip was only about Mach 0.76 according to your numbers. But with a tailwind, you can get more efficient flight (fewer pounds of fuel per mile) by flying slower and letting the tailwind carry you forward.
Going into a stiff headwind you want to fly much faster to reduce the amount of time you're fighting that headwind.
(This is oversimplified, because the altitude also affects the optimal cruise speed, but the optimal cruising speeds tend to be greater in a headwind than in a tailwind.)

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What is the optimal way to climb fastest between two points on a Cessna 172N?
Cessna 172N’s POH has Vx = 59 Knots.
Let’s assume you need to climb from 1000 msl on traffic pattern just after you finished turning cross-wind and are clocking 85 Knots, to 2000 as fast as possible, say to clear the noise restriction zone.
Is it better to let the plane get to some 100 Knots then pull back and climb or just start the climb right away?
As an example practicing full speed stall maneuver I have noticed I climb at a rate of 1500 feet/min while on Vy my rate is never more than 650 feet/min.

If you want to climb fast you should be climbing at Vy (maximum rate of climb), if you want to climb at the best angle, you climb at Vx (maximum climb angle). Vx is usually used for obstacle avoidance. Since if I remember right, Vy is about 85, you should climb immediately.

Obviously, a non-sustainable climb can exceed the maximum climb rate that you can sustain. By immediately pulling up an decelerating to Vy, you'll still get the maximum non-sustainable climb as you drop to Vy, and then you'll get the maximum sustainable climb. How can you do any better?

What's better ? Shorter in time ? Distance travelled ? Fuel consumption ? Safety ? Confort ?

Ron nailed it. (See comment on OP.)
It depends on what you’re trying to achieve.
Climbing “fast” in terms of maximum vertical speed = Vy (best rate)
If the noise sensitive zone is immediately surrounding the airport, you want to use Vy to put altitude under you as quickly as possible.
Climbing “fast” in terms of maximum feet per nautical mile = Vx (best angle)
If the noise sensitive area is a few miles away, you may want to use Vx to get to altitude before overflying the zone.
I gather from the question that the noise sensitive area is right next to the airport.  If that’s the case then Vy is likely your best option.
While accelerating to 100 and then pulling up feels satisfying, just pitching for and holding Vy (or Vx) is more effective.  Peter’s answer explains why this is.
In any case, watch your oil temps (or cylinder head temperatures if you have a CHT gauge) and prioritize keeping the engine cool over noise abatement.  While being a good neighbor is important, taking care of the engine and flying safely is even more important.

Aircraft drag scales with the power of speed. This by itself should make clear that deviating from the point of optimum performance will always incur higher losses which cannot be made up for later.

Let P₁ and P₂ be polar points away from the optimum point $\text{P}_{opt}$ along a quadratic drag polar. No matter how you interpolate between the two points (red line), you will never look as good as when staying at the optimum point all the time.
OK, it seems that even this description is not obvious enough for some people. Dear down voters, I am now typing this especially slowly so even you can follow: No, going fast first and then pulling up will not help. It is better to stay at the speed for the best climb angle all the time.

I would +1 your answer again if I could.

I dont know if we are talking about the samething? I have had encounters with cowboy GA flyers who have just appeared from nowhere over the ridge of Santa Suzana near Van nuys airpot. I have learnd to keep calm and continue level flight or even descend a bit to let the wind rush over my wings then pull up fast and climb over traffic to avoid potential collision. You wouldnt have sluggish controls and get immediate positive control authority. This will lift you 300-400 feet really fast. Howevr for sustained climb to your flight altitude you want to follow the POH. My question was not that.

@kamran - another pilot keeping visual seperation from you is not expecting you to do any of that and may require HIM to take evasive action to avoid YOU (and label you a "cowboy pilot")! Right of way rules are already well defined in 91.113. Non-standard evasive maneuvering is a matter of last resort only. A slight turn off course is by far the preferred option. You may want to review collision avoidance guidance in AIM 8-1-8, specifically 8-1-8(c)(d)(e).

@acpilot, The prime rule of aviation is not to crash! Santa Susana pass, Magic Mountain pass, New Hall pass and a few more in my area are natural bottlenecks of a congested VFR traffic to one of the busiest airports in the world, Van Nuys. We have had three fatal crashes over just last few month. I certainly hope somebody learns from my real life experience and avoids a disaster!

@kamran: Your question asks for the fastest method to climb from 1000 ft to 2000 ft. If the clock starts ticking at the point you decide to change altitude, the time to accelerate must be included. Then your Cowboy-style popup takes longer (and everyone around you by surprise, I might add). Allow me to not follow your recommendation.

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How can a military combat pilot indicate surrender?
If a military pilot is captured by an enemy, how can he indicate that he has run out of ammunition to engage in combat or is not in a position to retaliate? Does he use lights, radio, and/or flares?

The question is stil unclear to me:
If a military pilot has been captured by an enemy, he/she's being held prisoner in a way or another.
On the other way, if the crew is still in the aircraft, the only scenario i can think of is a pretty large aircraft (transport/tanker, SIGINT/ELINT, AEW, ecc) being intercepted by one or more fighter aircraft like in event of an airspace violation.
In an event like that, I think standard signaling (like wings waving, nav lights flashing ecc.) can occur.
Otherwise, if I'm in a maneuverable plane, why not trying to go defensive and evade incoming threats?

It needs two for a successful surrender. You would need an extraordinarily principled opponent - most enemy pilots would relish the chance of an extra kill with no risk.

just asked in Politics SE: Can a jet fighter "wave a white flag"?

There is no universally accepted means of surrendering an aircraft. According to Humanitarian Policy and Conflict Research at Harvard University,

Aircrews of a military aircraft wishing to surrender ought to do everything feasible to express clearly their intention to do so. In particular, they ought to communicate their intention on a common radio channel such as a distress frequency.

They can do other things like rocking the wings, jettisoning the weapons, flashing navigational lights etc. However, none of these are universally accepted or even have a clear meaning in the heat of combat. So the best course of action will be to bail out.
If a pilot is captured by an enemy, there would be no need to surrender.

Lowering landing gear is also often considered a sign of surrender. A combination of dramatically slowing, turning navigation lights on, dropping landing gear and rocking the wings will likely signal clearly enough that you intend to surrender... if the enemy can see you. In the age of guided missiles, however, they probably won't. The best surrender is to be out of the aircraft and clearly no longer a threat.

I just had an idea: what about turning on the transponder? Provided the aircraft is equipped with one, of course. Surely, broadcasting "here I am, shoot me if you want!" is going to get the enemy pilot's attention, and hopefully in the right way.

And will likely get you shot!

If the pilot engaged in combat, and simply ran out of ammunition, surrendering isn't something that has to be accepted by the opposing party. The rule is, you need to surrender on first sight of the enemy. Once you engage in combat all bets are off and you can be destroyed even if you release the canopy and throw up your hands (not recommended!) See, people get a peculiar sentiment when you shoot at them. They appreciate that you missed, but they don't take kindly that you offered surrender after you go winchester on the missiles and bullets.
Also, while you are surrendering. Assuming you didn't engage in combat, consider learning the other side's language and make sure you surrender in a top of the line aircraft. For example, Viktor Belenko defected in a Mig-25 in 1976 by flying it to Japan. This was a very valuable aircraft which he traded for a carton of American cigarettes and a million dollars. (ok just kidding, but he did get a nice trust fund set up for him when President Ford accepted his asylum plea.)

Generally theres no surrender bail out, In the pacific theater during the Second World War there was no aircraft surrenders. In fact even if the pilot chose to bail out of his aircraft (American Pilots) they would be strafed while in their parachute, and even if they had made it to the water. ( Japan did not sign the Genova accord) For this reason many American pilots returned the  favor and would go so far continue shooting at the already critically damaged Japanese fighter.

Hi and welcome to the site. Do you have any sources to back up those claims you make?

One reason to keep shooting at Japanese aircraft that were clearly damaged was that the Japanese had a tendency to suicide by ramming something as long as they had any control left, not because the Americans were cold blooded killers out for revenge.

In WW2, USAAF bombers would some times signify an intent of the aircrew to bail out of a shot up bomber, by dropping the landing gear. The hope was that the attacking fighters would stop shooting, and not kill more of a crew that was just trying to get out and would be captured upon reaching the ground.
This was not official policy on either side, but it was occasionally done, and occasionally respected.

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How strictly are language rules adhered to between Pilot and ATC?
My understanding is that there are general sentence structure rules that must be adhered to when there is contact between Pilot and ATC are well defined, like this.
Are these rules strictly followed in the real world, and is all other conversation fully avoided?
If not, does it happen often enough to be considered while designing an automated ATC response system?
(Based of videos of pilots sharing lighter moments with the ATC on YouTube)

Related

related

Your second question (automated ATC response) should be separated from your first question (strict phraseology).

Standard Phraseology is what should be used, but especially in those countries where the local language is an allowed IFR language, you will get deviation from that in daily use, either due to dialect, accent or simply colloquial terms influencing the phraseology used between pilots and ATC.
In countries like the USA, where English is the local language anyway, you will sometimes hear non-standard phraseology being used. In countries like Germany, where English is not the local language and IFR is only allowed in English, you will have pilots and ATC adhering to standard phraseology more closely, especially to avoid misunderstanding due to local accent.

Anecdotal comment: I fly in Germany and usually use English also for VFR. Germans have a very phonetically hard sounding pronunciation in English, making the language sound clipped and sharp, which carries over to phraseology being used. Many native English speakers have commented though that this makes it really easy to understand, because every word is spoken very distinguishedly. Although I speak English fluently without accent in normal day use, I tend to slip into a German accented English in aviation... because it's easier to understand.

"Germans have a very hard sounding pronunciation in English" Oh well, you never heard french pilots speaking english over radio, did you ? I would say that German pilots are rather ok, compared to French (and I'm french...)

@kebs I have, plenty of times. But to me, Germans are easier to understand due to the hard pronunciation, whereas the French... are not...

@kebs I think perhaps you interpreted the word hard as difficult, rather than not soft. French-accented English softens a lot of consonants and elongate some vowels, whereas German tends to emphasise certain consonants and produce a rather "clipped" tone.

Ah, @kebs, I have corrected my answer, I mean hard as anaximander describes it, as phonetically hard, and not difficulty hard. My apologies, if this was unclear.

Bottom line: we do agree...

"hard sounding pronunciation" that explains the stereotype pretty well. Useful to know it's just an accent thing. :)

@Joshua German itself is very hard sounding and not as soft as other European language.

Over the telephone, I've always thought that the English accent of Hindi speakers was actually easier to understand than American accents

Here in Kuwait, Arabic phrases can commonly be heard over the normal ATC chatter; and the air is thick with heavily accented English.

Adding to @BurhanKhalid's comment above, apparently in Sweden, even when nominally using English some Swedish phrases (such as good morning/afternoon/evening/etc.) are often used. Not enough to impede understanding, but certainly enough to stand out in communications.

No, deviation is not fully avoided, but it is mostly avoided. As a product of good airmanship, we are taught that superfluous chatter over the comms is to be avoided.
Remember that the type of comms used by ATC is one way - if someone is talking then nobody else on that frequency can, so some pilot with lots of extra chatter or pauses will be blocking up communication.
There's nothing worse than listening to this

er Golf Alpha er.. Bravo Charlie er Delta is a Ceeeeeesssssna 172 flying er.... Elstree to uhmmm... Cranfield at twooooo thousand fiiiiive hundred feet on QNH er.... 1010 and uhm... we're currently (where are we dave?) abeam errrrr Aylesbury....... we uhmmm.. request Basic service and uhmmmmmm *break*.

When all you want to do is request a Zone transit because you're getting close to a zone.  (Note that that is all pretty much standard phraseology, just delivered badly - but it illustrates my point)
Anecdotally, I do deviate slightly, ofen giving a very quick "Thankyou" or "Good day" when changing frequency from a controller who has provided me a useful service en-route - This is a fairly standard deviation used by many pilots. I tend to even avoid this if I can tell that they are busy, and stick with the short, sharp  and standardized "Changing XYZ Approach 123.45".


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What criteria do FAA VFR Charts use for High-Intensity Obstruction lights?
FAA’s website provides some symbology explanation (specifically, I’m looking at VFR Charts) and also a database of obstacles, the Digital Obstacle File (DOF). Their PDF provides an explanation of the lighted codes; options of R, D, H, M, S, F, C, W, L, N, U.
I assume that VFR Charts are created with the same data as the DOF. What are the lighting codes in the DOF that correspond to the “High Intensity Obstruction Lights” on VFR Charts?

The DOF_README.PDF includes the following field description:

Type of Lighting
"R": Red
  "D": Medium intensity White Strobe & Red
  "H": High Intensity White Strobe & Red
  "M”: Medium Intensity White Strobe
  "S" : High Intensity White Strobe
  "F" : Flood
  "C" : Dual Medium Catenary
  "W": Synchronized Red Lighting
  "L" : Lighted (Type Unknown)
  "N": None
  "U": Unknown

Since the charting would only use the "High Intensity" label if it was known, it would map to types H and S.
It's also useful to note that the Aeronautical Chart User's Guide adds the following note:

High-intensity lights may operate parttime or by proximity activation.

i think your second line lost a linebreak, did you mean H and S would be the types ? if so, my limited amount of cross-referencing the charts and DOF would agree.

@user320781  You are correct about the linebreak and the types. Answer has been edited.


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May I fly with passengers on a homebuilt experimental airplane with only a simple PPL?
So I’m in the market for a small two-seater. I see a lot of homebuilts and experimentals listed that are perfectly priced. I have my private pilot certificate but that’s it.
Would I be able to fly an experimental with a passenger?
Do I need something special if I wanted to buy one of these planes?
Currently I live in Ohio, United States.

You should list your jurisdiction as the answer to this will vary depending on where you are.

The short answer is 'yes, you can carry passengers', but I'm unsure how to expand that into an answer worth posting.

Yes, you can, you don't need anything other than the words EXPERIMENTAL to be visible by the passenger. Your PPL is fine for flying experimentals, although like any other aircraft change, I would get instruction from an experienced instructor in that type/model before going solo. Experimental aircraft can have some pretty different handling characteristics.
So, from a regulations standpoint, you are looking for CFR 91.319: Aircraft having experimental certificates: Operating limitations.. According to (j) of that:

No person may operate an aircraft that has an experimental certificate under § 61.113(i) of this chapter unless the aircraft is carrying not more than 6 occupants.

So you can have up to 6 occupants (including the pilot).

Do I need something special if I wanted to buy one of these planes?

No, your PPL allows you to fly experimentals, but as I said above, please get training from an instructor familiar with the aircraft and its handling characteristics. Many dear departed pilots probably wished in the last moments that they had some formal training in the experimentals they bought. You should also get somebody to go over the aircraft mechanically that is familiar with that model. Also look into your insurance costs, the airplane may be cheaper, but your insurance will probably be more expensive.

Your insurance may also mandate instruction (often 5 or 10 hours but it can in theory be any amount they want) in the aircraft prior to carrying passengers if you have no time in type.

Does the rule of 3 takeoffs and 3 landings still apply if you haven't flown within 90 days?

@TayE yes, currency requirements do not change based on certified or experimental.

Depending upon the aircraft, you might need a high performance or a retractable gear endorsement, or a conventional gear endorsement.

I've never heard of those endorsements. Retractable gear is a complex endorsement, but if it doesn't have a constant speed propeller and adjustable flaps you don't need it, I've never heard of any endorsement for conventional gear. Depending on the aircraft you could need any of the endorsements available including tail wheel, sea plane, high altitude/pressurized, turbine, etc.

Conventional gear might be another name for tailwheel.

It's a sub $10k experimental that barely goes 90mph. If this thing needed any special endorsements I'd be shocked lol


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How much training does an A320 pilot need to fly an A321?
From flight simulation and from pictures, it appears that the cockpit of the  A318, A319, A320, and A321 have few if any differences.

Could an A320 pilot fly an A321 without further training?
If not, how much training would he need? Maybe he has to practice landing, because of the different length of the aircraft.
What big differences in the cockpit do those planes have?

From Flight Training International:

Airbus A320 Type Rating

The Airbus A320 family of jet airliners consists of five aircraft:       the A318, A319, A320, A321 jet airliners and ACJ business jet.
Only one type rating is required to fly these Airbus aircraft, as       they have similar flight decks.
To earn a type rating for these Airbus aircraft requires the    completion of a technical course that lasts anywhere from 8 to 12 days depending on your pace.

So the answer from a regulatory point would be no additional training.  Some airlines might have policies that require a minimal check, probably in a sim.

"Some airlines might have policies that require a minimal check, probably in a sim." Do you happen to have a source with this?

@Mast  Not as direct example of where it is required.  I state is a possibility as each airline operating under Part 121 (in the US) is required to have a training program defined and approved by the FAA.  The requirements for the program are covered in Part 121, Subpart N.  These allow for significant variation between airlines as long as they meet the minimums.

As the typerating is a A318/19/20/21 typerating you are allowed to fly the whole A320 series without further training.

Could an A320 pilot fly an A321 without further training?

Legally, yes. Airlines may want a check ride to make sure the pilots are aware of the correct rotation angles—A321 tail-strikes around 12°.

If not, how much training would he need? Maybe he has to practice landing, because of the different length of the aircraft.

Depends on the airline, but probably that (in a simulator—you don't take a transport jet out just for training).

What big differences in the cockpit do those planes have?

A placard somewhere.
A321-100 will have different fuel system switches, because it's tanks are not split to inboard and outboard. A321-200, the one with winglets, should have the same wing—and fuel system—as the rest of the series.
Engine instruments show different values depending on what engines you have (RR and IAE ones show EPR, the others show N1), but that is just the symbols on the screen.
There may also still be some early aircraft around that still have CRT displays with slightly different graphics—the graphics was simplified with switch to LCDs.
That's about all differences there are.


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How can I calculate the rolling moment of an aileron for a given plane based on its performance?
Let's say I have an already-built airplane with known basic characteristics like weight, wing span and wing surface, and I can measure the time of all possible manoeuvres at different speeds.
How can I calculate the roll moment of an aileron in its maximal deflection? The precision of hundreds of [kg*m] is sufficient.

If you know the rolling speed at a given flight speed, you can calculate the aileron effectiveness and use that to calculate the forces. The final rolling speed is reached when roll damping and the aileron-induced rolling moment reach an equilibrium: $$c_{l\xi} \cdot \frac{\xi_l - \xi_r}{2} = -c_{lp} \cdot \frac{\omega_x \cdot b}{2\cdot v_\infty} =  -c_{lp} \cdot p$$
Thus, your aileron effectiveness is $$c_{l\xi} = -c_{lp}\cdot\frac{\omega_x \cdot b}{v_\infty\cdot(\xi_l - \xi_r)}$$
The roll damping term is for unswept wings $$c_{lp} = -\frac{1}{4} \cdot \frac{\pi \cdot AR}{\sqrt{\frac{AR^2}{4}+4}+2}$$
and the moment per aileron now is $$M = c_{l\xi} \cdot \xi \cdot S_{ref} \cdot b \cdot q_\infty$$
Calculate the moment for each aileron separately; normally the left and right deflection angles are not exact opposites, which helps to reduce stick forces.
If you only need an approximation, maybe do it like this:
You first need to have all dimensions and the deflection angles. I expect you don't have lift polars of the wing section, so you need to approximate the lift increase due to aileron deflection with general formulas. This is $$c_{l\xi} = c_{l\alpha} \cdot \sqrt{\lambda} \cdot \frac{S_{aileron}}{S_{ref}} \cdot \frac{y_{aileron}}{b}$$
and the moment per aileron now is $$M = c_{l\xi} \cdot \xi \cdot S_{ref} \cdot b \cdot q_\infty = c_{l\alpha} \cdot \sqrt{\lambda} \cdot \xi \cdot S_{aileron} \cdot y_{aileron} \cdot q_\infty$$
Nomenclature:
$p \:\:\:\:\:\:\:\:$  dimensionless rolling speed (= $\omega_x\cdot\frac{b}{2\cdot v_\infty}$). $\omega_x$ is the roll rate in radians per second.
$b \:\:\:\:\:\:\:\:\;$  wing span
$c_{l\xi} \:\:\:\:\:\:\;$  aileron lift increase with deflection angles $\xi$
$\xi_{l,r} \:\:\:\:\:\:$  left and right aileron deflection angles (in radians)
$c_{lp} \:\:\:\:\:\:\:$  roll damping
$c_{l\alpha} \:\:\:\:\:\;$ the wing's lift coefficient gradient over angle of attack. See this answer on how to calculate it.
$\pi \:\:\:\:\:\:\:\:$  3.14159$\dots$
$AR \:\:\:\:\:$  aspect ratio of the wing
$\lambda \:\:\:\:\:\:\:\:$  relative aileron chord
$S_{aileron} \:$  Surface area of the aileron-equipped part of the wing
$S_{ref} \:\:\:\:\:$  Reference area (normally the wings's area)
$y_{aileron} \:$  spanwise center of the aileron-equipped part of the wing
$v_\infty \:\:\:\:\:\:$ true flight speed
$q_\infty \:\:\:\:\:\:$ dynamic pressure

Depending on the relative chord length of the aileron, this formula is good for maximum deflections of 20° of a 20% chord aileron or 15° deflection of a 30% chord aileron. Remember: This is a rough estimate for straight wings.

What are the units in the first equation? The right hand side appears to have units of [seconds], assuming p is dimensionless, while the left-hand-side appears to be dimensionless.

@supergra: No, it's dimensionless. I just realised that I confused p with $\omega_x$ in the first two equations. Thank you for finding this mistake!


text:
How is the synchronization of multiple engines managed in twin engined aircraft?
If one of the two engines of an aircraft is running at slightly less RPM then the other, how the synchronization is being managed?
Also, if there are more than 2 engines in the aircraft, how that will effect?


text:
Does every Safety–of–Flight Test (SOFT) include full testing of each and every equipment?
Does every Safety–of–Flight Test (SOFT) include full testing of each and every equipment with the full EMC or is it just a basic quality test for some of the affected systems?

Safety of Flight (SOF) Testing is a sample, a subset, of a more exhaustive set of tests.1 It evaluates critical functions that "assures basic" levels of safety for critical components of the system.
The FAA further defines "critical" in this way:
   Usually a function whose loss would prevent the continued safe flight
   and landing of the airplane.2
Though the definition is somewhat circular, it is usually clear when a function is not critical, not required for safety of flight.  For example, a Terrain Awareness and Warning System (TAWS) is not required to be installed, therefore, it's function would not be part of the SOF testing.  However, attitude display, engine instruments, and airspeed are all defined in 2 as critical and would be part of SOF testing.

You are confusing SOFT with functional testing and development assurance level (DAL). If you quoted from your reference 1, you'd have: "SOF assures basic pilot safety. Tests are shortened versions of qual tests in the areas of structural integrity, thermal and electrical safety, operation in explosive atmospheres and during explosive decompression."  These are tests to ensure the hardware does not pose a hazard to the aircraft or crew. The function of the component has no relation to SOF. SOF only assures that it won't break something else on the plane. Flight test tests the function.

We disagree, and I assure you I am not confused. If the engine does not function, it clearly affects SOF.


text:
Why are voice recordings stored and not transmitted?
With today's technology, why are voice recordings not transmitted, saved somewhere in case a disaster does happen?
Let's say a plane goes missing, they can spend a long time trying to salvage the black box, thus could take years to find out the real cause of the problem. Surely if the data was transmitted, stored somewhere, the investigators could then use this information to clearly determine the cause and highlight any technical failure to help prevent such things happening again.

We've had a similar discussion after MH370. Those answers cover this question, too, so I vote to close this.

The simple answer is: Because 1/ there is no free datalink available over the largest part of the world, which happens to be oceans, deserts and mountains, 2/ there is a large volume of bits. The lesson has been learned from AF447 and MH370, and new solutions with satellites will soon retransmit ADS-B broadcast to the ground. However ADS-B broadcasts only few information (far from the content of the recorders), but sufficient for search and rescue operations (including a GPS fix).


text:
Why is Concorde no longer in service?
The crash of the concorde resulted in many deaths, but the crash was never caused by the concorde but by a plane that took off before it. Also airliners like the Boeing 737,747,and 777 have had accidents resulting in all deaths of the passengers and crew and was caused by the airplane, but are still in service today, so why are those airplanes still in service after the accidents and the concorde not in service after its accident that wasn't even caused by the concorde?

The crash was never caused by the Concorde. The failure had been latent until that day. The fire was caused by a Concorde's wing fuel tank rupture consecutive  to the overpressure caused by the impact of a Concorde's tire fragment. The external cause comes only at the tire destruction level. Indeed any cause resulting in a tire explosion could have triggered the same chain of consequences.

The crash was only one of the (albeit an important) reason for the grounding of Concorde. Actually, the aircraft was retired around three years after the crash. The main reason was that not enough people were flying it to keep it profitable.
The Concorde as a technological marvel, but it had a number of disadvantages:

The aircraft was costly- The program cost over $3B and produced 20 aircraft, of which 14 were used in commercial service.
Maintenance costs- The small number of aircraft and technological sophistication meant that the cost of spares was high and options limited.
Operating costs- The Concorde consumed nearly three times per passenger fuel when compared to the Boeing 747-100. Still, the aircraft made operational profit due to the high cost of tickets.
Recession- After 9/11 attacks exacerbated the global downturn in aviation due to recession, there was an enormous drop in first class air travel, on which Concorde was dependent on.

While announcing the retirement, British Airways cited

commercial reasons, with passenger revenue falling steadily against a backdrop of rising maintenance costs for the aircraft.

This podcast covers the topic pretty closely and is a great interview with one of the old pilots of the Concorde. From his accounts the Air France Concorde crash was the last straw that lead to its shut down but was not the only factor.
The Concorde itself was, in its prime, a very profitable airplane and made BA and Air France loads of money when they flew it. However the plane was extremely costly to operate. Due to its supersonic nature the air frame saw a great deal more fatigue than a subsonic plane and it became not only expensive but time consuming to maintain the aircraft. All the while regular jets got bigger while the Concorde did not. Consider that the plane had a 100 person capacity while jumbos kept getting bigger. In turn the smaller margins jumbos made per person were beginning to catch up to that of Concorde (for what it's worth it's a pretty old plane). Much of this lead to its demise. Along with that, the down turn in air travel after 2001 lead to a big passenger slump which did not help keep the very expensive and rapidly aging plane in the air.
On an interesting (and similar side note) check out the Boeing SST which was a similar plane that never made it to production for similar reasons.

Mainly for three reasons:

Increased maintenance costs.
Low number of passengers after the accident of July 25, 2000.
The decline in air travel following the September 11, 2001.


text:
What is autofeather for?
What is autofeather and when is it used?

Related: Autofeather on Wikipedia. I believe you don't use it, it's automatic.

@mins Can't it be enabled/disabled on some aircraft? Perhaps that's what is meant by "used".

@Steve: Yes, e.g. on the Beech SKA 350, there is an autofeathering switch and a manual feathering on propeller levers. Overall autofeather enters in action when armed and the propeller starts generating more drag than thrust. Source and additional information.

Autofeather is an automated feathering feature, common in a lot of turboprops, which automatically feathers the propeller on an engine if it loses power without having to either pull the power or propeller lever to feather the prop.
It reduces crew workload in the event of an engine failure and, as a feathered propeller greatly reduces parasite drag on the side of the dead engine, reduces the asymmetrical thrust yaw moment about the vertical axis of the airplane.
It is particularly useful during takeoff and landing operations where airspeed may be very close to minimum controllable airspeed on one engine.

You could make it even better by explaining what feathering is?


text:
How do pilots maintain awareness of other airplanes during taxi?
If I compare taxiing of airplanes with, for example, driving cars, drivers in the latter case regularly check the positions of their cars relative to others by using the different available mirrors. However, that is not an option in airplanes.
Just thinking about all potential possibilities, I imagine that airplanes probably rely on the airport control tower for making decisions that require the knowledge of the relative positions of other airplanes. Also, collision–prevention devices provide part of that information.
My question is:
How are airplane pilots aware of other nearby planes during taxi? Do they need that information, or is not useful for them as instructions are sent by the control tower?

Are you thinking of large, towered airports or small untowered airports?

@raptortech97  I did not think that there was a difference between both. I am curious, why is that different? Small airplanes mean actually small size planes as well, does it?

It would appear they aren't aware of eachother in Dublin... and it wouldn't be the first time there either.

I know the British Airways taxi procedures.  If one pilot needs to "look down" to complete a checklist, program something into the FMC etc, there is a positive check that the other pilot is looking out of the windows.  At no point should they be taxiing without a good visual lookout.  "See and be seen".

"car drivers are checking regularly the position of their car relative to others by using the different mirrors available in the car" - my experience in many different places is that this is substantially not the case, though I wish it were.

At a large airport, all aircraft movements are coordinated by the ATC tower on the ground frequency. Aircraft should never move without authorization from the controller. The tower will issue instructions to aircraft that might look something like this:

Taxi to Gate 1 via Alpha, Alpha 1, Lima 3, cross runway 24, hold short Delta.

These names correspond to markings on the ground that match up with the airport taxiing maps. By talking with the pilots, the controllers are able to build up a map of where aircraft are. It also helps that they can look out the window and see the aircraft on the ground.
At airports without a tower, taxiing isn't much of an issue. There aren't many planes around, and there's generally only one runway and not many taxiways. Nevertheless, aircraft taxiing when there is no ground controller comply with "see and be seen" by looking outside and turning on aircraft lights. Furthermore, if the aircraft has a radio, it should self-announce its movements on the ground.

So pilots are taxiing "blinded", following instructions of controllers like board game? (conceptually I mean :) )

@TrebiaProject. Basically. Obviously, if they see a plane ahead stop they're not just gonna ram into it because the controller didn't tell them not to, but they more or less just do what the controller tells them to. They're almost like chess pieces.

@Trebia: Pilots can still look out their windows and see where they're going. There's not the same need for mirrors to look backwards etc. as there are for cars, because taxiways are single-lane anyway -- there's no overtaking.

@raptortech97 thanks! I think now I understand. I think if pilots have more information (for example the locations of the aircrafts are shared with the pilots) that will allow having an extra double checking. Is it frustating for the pilots this situation? I will be interested in understanding from a pilot perspective this situation, but is opinion based :)

@HenningMakholm still some incidents happen because ground operations. The more people looking to the information, the best. I was thinking as well measuring distance, I remember a couple of incidents where a wing hit the tail plane of a parked airplane. Thanks!

@TrebiaProject. I can't help you there. I love airplanes, but I've never been behind the wheel of one.

@TrebiaProject. In short - not particularly frustrating. It's kind of opinion-based, so perhaps not a great question topic - but please feel free to join us in chat to discuss!

Most of the time, the taxi patterns are such that there's little conflict.  E.g. if your FBO is about midfield, you taxi from there to the end of the active runway and take off.  Landing, you probably leave the active somewhere past midfield - especially if you see another airplane moving the opposite direction on the taxiway :-)

I think the answer would be improved by adding movement/non-movement ateas

To expand on the answer from raptortech97, taxiing an aircraft is similar to driving a car. Instead of traffic signals, the ground controller tells the pilot where to go, but the pilots should still be looking out the window and remain aware of aircraft around them. As with aircraft in the air, the ground controller will anticipate conflicts between aircraft and give them instructions to avoid issues.
A controller will instruct an aircraft when they need to yield to others:

...give way to company 737 on Delta.

And possibly advise the other aircraft as well:

...continue on Bravo, company will give way to you at Delta.

Often aircraft are going to the same place (like the active runway), so it can simplify things to just tell pilots to follow other airplanes:

...follow the company 737 on Delta.

In conditions where aircraft will be taxiing, visibility is generally good enough that pilots can see other aircraft. If visibility gets worse, the ground controller will be more cautious, knowing that the aircraft may not be able to see each other.


text:
How to find out if Restricted Area is "hot" before taking off?
For example, I often fly from KCHO to KOXB and almost always get cleared through R-4005 and R-4006. Occasionally they will be hot and I will have to go around, wasting time and fuel compared to if I had planned that route originally.
Is there anyway to call Patuxent Approach (or Washington Center) on the phone ahead of time to ask if the Restricted Area is hot?

Restricted areas that have scheduled times will be noted in the (sectional) chart margins. In this example you'll find this at the bottom of the Washington sectional chart:

Ones without regularly scheduled hot times will say something like 48 hrs in advance or other times by NOTAM.
As you've noted though restricted areas with posted hours may not always be "hot" during those hours - sometimes you get lucky. The best way to check if you're going to be lucky prior to departure is to ask Flight Service (1-800-WX-BRIEF): The briefers have access to the same data as ATC, and will know definitively if a restricted area is hot (at least as of the time you call them).
Obviously you should still call the controlling agency when airborne to verify the status of any special use airspace prior to entering it (briefers can make mistakes, and some restricted areas may be activated on short notice which means they may go hot while you're enroute).


text:
Is QDR = QDM ± 180 always true in the case of an NDB?
If the magnetic variation at the aircraft and at the NDB station is different, then magnetic bearings would also change, so QDR = QDM + 180 would not be true. Can someone please help me understand this?
For example:

The True bearing to NDB is 090 degrees, so the true bearing to the aircraft will be 270 degrees
Variation at NDB is 10 degrees west
Variation at aircraft is 20 degrees west
So magnetic bearing to NDB will be  110 degrees and magnetic bearing to aircraft will be 280 degrees

Clearly these are not reciprocal of each other.

I’m tempted to wade in here, but you seem to have a high level of knowledge and IQ, so I am puzzled at your confusion.  Because the short answer is that they aren’t necessarily the reciprocal of each other, and the reason is MagVar.  As you point out in your well thought out question!  Is there something still unclear?  (BTW, true bearings aren’t alway the reciprocal of each other either, but for different reasons…)

@MichaelHall in the books it's mentioned they are +-180 reciprocal of each other. which isn't true as you can see

Can you cite a reference?  I think context is important, because from a practical standpoint they might as well be reciprocal.

QDM and QDR are abbreviations from Q code. Originally:

QDM: The magnetic heading for you to steer to reach me (or ...) with no wind is/was ... degrees (at ... hours).

QDR: Your magnetic bearing from me (or from ...) is/was ... degrees (at ... hours).

Actual determination of QDR and QDM according to Q Code
From these definitions it is clear the location used when determining heading for QDM and bearing for QDR is not the same, so if the variation is different the angles won't be reciprocal.
However this is not this convention which is used when talking about QDR/QDM with navaids.
NDB
A NDB station broadcasts no bearing information. So the aircraft ADF actually determines the QDM by sensing the transmitter bearing relative to its local magnetic north.
If a QDR is needed in this context it will not be computed using the actual variation at the NDB location, it will be the reciprocal angle QDR = QDM + 180°.
If the variation changes on the route to the NDB, the ADF will show an updated QDM, and the heading will be adjusted. At the end the route will reach the NDB, though the heading will have changed on the route.

ADF: Actual QDM sensed by ADF, QDR reciprocal of QDM
VOR
The VOR signals carry the QDR information. The VOR indicator displays this information. The broadcast angle is based on the VOR own magnetic north.
The QDM which the VOR indicates is just the reciprocal of the QDR. Therefore if the variation at the aircraft location is different, this QDM is wrong. This is the reason why it's clearer with VOR navigation to talk about radial to/from rather than QDM/QDR.

VOR: Actual QDR broadcast by the VOR, QDM is the reciprocal of QDR

"VOR airborne equipment receives phases of two different signals (reference
and variable) and derives QDR by taking the difference between the two. Its
reciprocal is QDM. An RMI accepts relative bearings and not QDMs. Therefore the VOR phase difference giving QDM is first converted to give relative
bearing. This is achieved by use of a differential synchro in the VOR navigation unit which subtracts the aircraft's magnetic heading to give relative
bearing before the information is fed to the RMI. The RMI subsequently
adds the aircraft's heading to give the QDM."

So it's the relative bearing that gets wrong, correct?

I'm going through more references, Incase of an "NDB", it turns out that the QDM actually changes as the variation changes. While it is not the case for VOR. since the measurement is done at the Aircraft for NDB,  and for the VOR - i've explained the process how it goes

You guys are probably way smarter than me, but I thought the ADF was just a dumb radio receiver, and the needle simply points towards the non-directional signal. (kinda like a mag compass) Words like "determines" "approximated" "recompute" and "adjusted" imply some sort of programmable logic capability that I'm pretty sure they don't have.  I think the answer is misleading because of the use of these terms.

@MichaelHall Your comments are valid.

@mins Your answer is meaningful. It has given me relief. Thank you so much.

@mins can you also explain that - since the QDM is only approximate, wouldn't we start going away from the radial - and so see a deviation in the CDI ? Is this correct?

@mins can you pls explain the question in above comment? thanks :)

@SachinChaudhary: Yes it's correct. However the error will be tiny as the variation change is not so fast.

@mins: Thanks, your comments are helpful. Is that the reason that these concepts are not mentioned in aviation books for aircraft pilots? your knowledge is impressive. where did you get all this knowledge from?

@mins: can you please also answer this https://aviation.stackexchange.com/questions/90606/if-the-rmi-heading-rose-is-stuck-would-the-needle-still-display-correct-bearing?noredirect=1#comment245618_90606

@SachinChaudhary: Thanks for asking, but I don't have a better answer than the existing one. Try to be sparing with comments, they are for clarification only.

A statement that bearing from a station to the aircraft is the EXACT reciprocal of the aircraft’s bearing to the station is almost never true.  For either magnetic, (for the exact reason you describe…) or true bearing.  However, from a practical standpoint and as a general rule of thumb, it just doesn't matter.  The statement is accurate enough to consider it true for the purpose of navigation.
Considering your example, look at an isogonic chart and figure out how far you would have to fly to go from an area of 10 degrees magvar to 20 degrees.  If you were flying an aircraft with the range to make this flight you would likely have navigation equipment more sophisticated than just an ADF receiver.
Most GA aircraft that would need or want to home on an NDB are only going to cover an area where magvar varies by a few degrees.  Given the effect of wind, instrument accuracy, and pilot ability, trying to resolve for and accommodate the miniscule effects of the changing magvar just isn’t worth worrying about.
If you are a pilot, use 180 degrees if you need to figure the reciprocal for any reason, and don’t spend any time overthinking how you might want to adjust in flight.


text:
Why did the Swiss International Air LX40 (a 777-300ER) emergency land at Iqaluit airport?
Swiss International Air LX40 (a brand new 777-300ER) was en route from Zurich to LA on 1 Feb 2017 when one of the GE90 engines shut itself down because of data from its self-monitoring algorithms.
The crew decided to emergency land at Iqaluit airport on the southern tip of Baffin Island in Canada, which is extremely remote. Getting a new engine to Iqaluit and installed was an incredible odyssey in itself.
The photos of the incident are such that it seems that landing at Iqaluit and trying to do maintenance and take off again would be more dangerous than a diversion to somewhere larger like Nuuk in Greenland.

Given that the 777-300ER could have easily flown the remainder to LA with one engine -- which means it could have easily diverted to a nearby larger airport -- why didn't it? Are ETOPS rules so strict that you must land at the nearest airport and such that the nearest reasonable airport would not be permitted?

I know nothing about ETOPS, but Swiss may have their own operating procedures that applied here. And according to the Aviation Herald report the pilots were "puzzled" about why the engine shut down. As a general rule, if the aircraft systems start doing unexpected things and you don't know why, you want to get it on the ground ASAP before a larger problem develops.

Nuuk isn't much better...

The engine monitoring system shut down one engine, why would the pilots believe that the other one wasn't about to be shut down at any moment as well? The priority I'm sure was to get on the ground ASAP before they become a heavy glider.Figure out maintenance and getting back out later. In an emergency my thought process is just on landing, I don't care about maintenance and logistics until after I'm on the ground...

If diverting to Iqaluit were really that dangerous it wouldn't be allowed as an ETOPS diversion airport.

I very much agree with the comments that if you feel you may have a bona fide emergency, you need to land as soon as possible at an acceptable airport. Iqualt seems eminently acceptable: 8605' long, 200' wide (50 wider than the usual U.S. rwy), an ILS, and an air carrier airport which would mean emergency equipment. And, as previously commented, difficulties in maintenance after getting on the ground should not enter in to the captain's decision if he felt he had an emergency. Besides, there would no problem getting an empty 777-300ER off an 8605' long runway afterward. It was a good choice.

Keep in mind that it wasn't a computer that decided to shut the engine down in this mishap -- it was that the engine's fuel pump had come unhooked mechanically from its drive, causing the engine to die of fuel starvation.  ANY jet engine would have shut itself down if it failed in a similar way...

Kangerlussuaq is the only civilian airport in Greenland with a runway of comparable length to Iqaluit. There's also Thule AFB but that's much farther north.

The maintenance and subsequent take-off weren't more dangerous for the passengers than diversion to a more distant runway, because they weren't on board for those parts of the process. And the airline's first duty is the safety of its passengers -- its own employees come second.

You provide a bunch of links, and imply danger.  Where is the danger?  I mean, I see snow.  It is snow.  Frozen water.  Are you afraid of ... snow?

You say that replacing the engine was "an  incredible odyssey". In what sense would have things been easier in Nuuk? Or in any other airport?

Nuuk (BGGH) is much sketchier than Iqaluit (CYFB). Weather tends to be worse at BGGH, and the runway is less than half as long which could be a problem for departure. Kangerlussuaq (BGSF) would be a better choice than BGGH, but CYFB is fine.

Standard procedure for all twins is "nearest suitable airport"
If you're in a twin, and an engine quits (especially over a remote area like the Arctic), you set a direct course for the nearest suitable airport for your aircraft.  Issues like passenger comfort and availability of flights to rebook people are close to the bottom of the pilot's list in such a situation, as you've lost enough redundancy that continuing the flight is no longer an option (the next engine failure turns you into a glider).
Iqaluit-the-airport isn't as remote as you make it out to be
While the countryside surrounding Iqaluit and its airport is quite barren and rugged, largely isolating the city, the city itself is well-stocked with services for its size -- it is the territorial capital of Nunavut, after all.  It has a full hospital, fire and rescue services (in addition to the ARFF at the airport), and most of the other trappings of a reasonable city (it hosted the G7 finance meeting back in 2010).  In addition, most of the folks there speak English, and the city has a good track record in past diversion events.
The airport itself is also well-equipped -- it has a full air carrier runway complete with an ILS approach, ARFF services of its own, and scheduled air carrier service to Montreal, Ottawa, and Yellowknife as well as other destinations in the Canadian Arctic.  There's also a reasonably sized terminal building there, and full-time Customs staffing there that could slowly handle the passengers from such a diversion if the stranding extended for days.
Transpolar operators plan for this stuff
Operators who fly over the Arctic are required to have contingency plans for exactly this type of event.  Such planning includes being able to send a replacement plane in a timely fashion to pick up the passengers, having the ability to get parts out to the airplane-on-ground (AOG), and being able to perform maintenance in such a location or ferry the aircraft out if need be.  Coordination of rescue services (including cold weather exposure suits for crew), the ability to communicate with ATC and airline dispatchers, radiation concerns due to solar flares, and the ability to navigate where magnetic compasses are no good are all included as well.

As the operator of a twin engine aircraft, I disagree with your first point. I would choose an airport considering multiple factors including but not limited to: weather; terrain; airport facilities including runway length, instrument procedures, emergency equipment, passenger facilities, and maintenance facilities; and essential passenger accommodations outside the airport facility. In many cases I would gladly bypass an airport with a suitable runway to choose a suitable airport slightly further away.

@JonathanWalters -- yeah, I was a bit over-the-top with my wording there, thanks

For someone else's take on this see also: http://www.airliners.net/forum/viewtopic.php?t=733499

And for §121 operations, see §121.565. To my knowledge the FAA no longer offers an official definition of "suitable airport". No such requirement exists for §135 operations.

it's fairly amazing that they have street-view coverage of Iqaluit !  indeed, the airport is right in the town, literally touching the various hotels, town hall etc.

Given that the 777-300ER could have easily flown the remainder to LA with one engine -- which means it could have easily diverted to a nearby larger airport -- why didn't it?

Standard operating procedure for engine failure on a twin calls for emergency and landing as soon as possible. That was their closest diversion point at the time, so there they landed.
This is an instance of a more general rule that whenever all redundancy on a critical system is lost, it warrants an emergency and requires landing at nearest suitable airport. Continuing the flight on one engine would most likely considered reckless operation.
Regarding your suggested alternate, “somewhere larger like Nuuk” is definitely not true. Nuuk has runway of mere 3,117 ft, far too short for a 777. The 8,605 ft at Iqaluit is adequate, and it is the standard diversion airport for this area.
Plus it was at least 300 nmi further. You are not risking that when your gliding distance from FL360 is ~120 nmi (and there is no way one engine can keep you up in FL360, so it's more like FL300 and ~90 nmi) and you really can't be sure the problem that killed the one engine is not going to affect the other too.
Also, regarding the complicated repairs, there is no better place nearby. It is just as cold in the whole region and there are no heated hangars where a 777 would fit, so they needed the tent to provide reasonable working environment around the engine in the cold weather and would need it in any other airport in the region. That's why they have it.

Hey, sorry, I'm new around here.  What does FL360 & FL290 mean?  Googling it appears to just bring up cameras to buy.

@PopeyGilbert, “Flight Level” and the (pressure) altitude in hundreds of feet.

@PopeyGilbert Short answer: 36,000ft and 29,000ft. Longer and much more accurate answers here.

I was just wondering @JanHudec on a plane like that these days.  Does the computer system know at all times "the nearest field to divert to, if you have to divert" .. ?  Does that info appear when needed (or perhaps, it's just always shown at all times as you fly along) - what's the deal on that?  If yes, does the system understand subtleties like, which one is best based on your current heading, altitude and so on?  Or indeed do the pilots just have to quickly look up the nearest one; or they have it written down as part of a plan - or?  Cheers

@Fattie Sounds like a question to ask as you know... a question. :)

@Fattie I can’t speak for airlines, but I have been flying with Garmin handheld and panel GPSs since 2000 and they all have a nearest page that lists the distance and heading (actually bearing) to the nearest airports. You can set it up so that only runways of a specific length are displayed. I would imagine that the airlines have something similar.

While I'm sure Iqaluit was the right choice, Kangerlussuaq would have been a way more sensible option than Nuuk.


text:
How dangerous was this approach of a Dash8 Q400 really?
There is a video going viral here of a Dash8 landing during a recent media hyped storm:

According to the description and imagery it is a Dash8 Q400 (registration D-ABQD), Eurowings flight EW9203. It did land during a storm with alleged 110km/h (60 kts) crosswind on Düsseldorf airport.
According to https://www.flightradar24.com/data/flights/ew9203 it landed at 12:13 local time on 18.01.2018, runway 23L or 23R. Within the video it is claimed that there is wind up to 110km/h whereas other sources from other places claim more like 80-90kmh (43-40kts), it probably varied by the minute.
Wind direction seems to have been mostly from west, with storm typical quick variations.
The crosswind limit for the Dash8 Q400 seems to be 32knt, quite below any of the cited wind speeds, however given the angle difference (230 to 270) a cited wind speed of ~50knt would have been just within the limit.
TL;DR
If there was the possibility of going to another airport (I have no idea if there was), should the pilot have diverted to a less windy area for safety reasons?

I actually had a look here last night to see if this question would show up.  The first plane actually surprised me that they didn't go around - could have been gusts but it looked like some serious PIO just short of touchdown.  I've been in plenty of rocky rides in a Dash 8, of course - surely they're a tough little plane and can take a good beating but any Dash 8 pilots have a take on that?

"it probably varied by the minute" If that's the storm from last week, it varied almost by the second in some places. Peaks were high, people got lifted from the streets and boats lifted from the water. If the pilot had a window of opportunity, a moment of relatively low wind, making use of it is the best decision he could've made. The same place a couple minutes later may have been much worse.

They called this stabilized approach???

To be pedantic, that's a landing and not an approach. Approach usually describes an instrument approach.

I've seen (and did personally) much more rough-looking landings with gliders. Of course, gliders are shaken much more at much less wind strengths... Just to give a reference, one ended with the glider turning almost 90° to the right after touchdown, with a full left rudder. (managed to keep the wings in the air until a complete stop, so nothing was damaged)

That is a very nice landing!

The relevant TAF that the pilot would have seen before going there is below (only showing the bits for the time of landing):

TAF AMD EDDL 180929Z 1809/1912 22025G40KT 9999 SCT035
  TEMPO 1809/1813 26035G50KT
  PROB30 TEMPO 1809/1813 26045G65KT SHRAGS BKN015CB

So the pilot was aware of a strong cross wind possiblity, but even 26065KT is 27 kt crosswind (runway is 233) which is within the limits of the plane. So there was no reason to divert before getting there.
The metars just before and after the landing are below:

METAR EDDL 181050Z 27045KT 9999 SCT037 BKN043 08/00 Q0993 TEMPO 27045G55KT=
  METAR EDDL 181120Z 27034G48KT 9999 -RA SCT028 BKN038 07/01 Q0995 TEMPO 27045G55KT=

So the "baseline" was 27045KT, i.e. 27KT crosswind, and the maximum gust wind was 27055KT, or 33kts crosswind, just 1 kt above the plane limit.
Note that the metar wind indications are rounded to the closest 10 degrees, so the worst case could have been a wind from 274 degrees gusting at 55 kts, or 36 kts crosswind.
We can assume that the pilot decided to continue the approach based on the wind information provided by the tower.
Whether the pilot should have aborted at the last second because the landing was not going as planned is hard to gauge on a video, but based on the information we have, the wind parameters were ok.

I'm slightly confused here, you and @Federico are using different parts of the metar and coming to different conclusions about being just under/over the limit.

@DanNeely Looks to me like assylias is using the worst-case data to conclude that winds were just over the limit; and Federico is using best-case data to conclude that winds were slightly below the limit. (I'm still getting METARs figured out, so take this with an appropriate amount of salt.) When you're right at the edge of the allowed flight envelope, small differences like this can easily tip the scale to "above" or "below" the limit, with neither answer necessarily being wrong.

@DanNeely TEMPO is used to refer to expected temporary fluctuations in the conditions during the valid period of the METAR/TAF. So, while the prevailing conditions may have been 45 kt before the storm's arrival, during the storm it could have been 45 kt gusting 55 kt.

Well, tables for maximal crosswind is one thing and turbulence and stabilized approach a different thing.

I might close this one as it’s going to be opinion based.  The ‘danger’ of the approach is based upon a number of factors and not just pure numbers collected from an AWOS station on the field and a DEMONSTRATED crosswind component in a Q400 AFM.  It also requires factoring in ambient weather conditions in the area, worst case conditions which might be indicated by the meteorological information, company SOPs, pilot proficiency in strong crosswind landings, and aeronautical experience operating from a particular airport.
Is the approach risky in these conditions?  Yes.  Or, better put, the weather presents an increased consumption of crew resources and requires good discernment and judgment as to whether the crew is capable of safely executing the landing given these conditions.
Düsseldorf Intl. (EDDL) is notorious for high, gusting winds during storms, which is what makes it a favorite of avgeeks to go down there and shoot videos of jets struggling to takeoff and land out there in these conditions.  Given the historical treachery of the environment there, local METARS indicating thunderstorms in the area and gale force winds with gust factors as high as 20 knots, it’s a good guess that the environment at that airport that day would have really been pushing the boundaries of what would be safe or prudent for air carrier flight operations.  You also have to keep in mind the following.

The METAR data comes from an AWOS station somewhere on the field and can only measure the weather and wind conditions in its immediate vicinity.  This is not necessarily an authentic description of wind conditions on final approach or over the runway itself.
The METARs over the area do indicate the presence of thunderstorms in the vicinity and strong possibly of low level wind shear.  Add to this common conditions caused during weather like this at that airport ie turbulent air burbles and eddies across the approach flightpath caused by nearby terrain, buildings, etc., and the approach will almost certainly be difficult.
The flight crew’s proficiency and recency of experience in executing strong crosswind landings will have to be accounted for.  A Bombardier test pilot operating a brand new Q400 made a 34kt crosswind landing?  Fine.  It’s also meaningless here if this particular flight crew does not have the skill to land in those conditions as well.  How long has it been since this aircrew handled a strong gusting crosswind landings?  How proficient are they at this kind of a landing and do they have additional crew resources to handle additional contingencies should they arise?
And then there are emergencies.  Lose an engine during this kind of approach at or very near roundout and you could really be in deep trouble for maintaining directional control of the aircraft.

At the end of the day it’s up to the flight crew to make the call.  As a pilot myself and based upon these conditions at the destination combined with the responsibility for the lives of the 60 or so passengers in the back, I would have diverted to another airport.  Are the passengers not happy with that decision?  Give ‘em a free steak dinner and a travel voucher good for future flights on the airline and book them on a later flight to EDDL when the weather improves.  Better inconvenienced than in an accident.

+1 for actually discussing the dangers, rather than just citing wind measurements and published limitations. And for putting a high value on the safety of the people in your plane.

I would also agree this is too opinion based. Although the question could be reworded to ask what factors a pilot might consider when flying into known crosswind conditions, although I suspect such a question has probably already been asked.

According to https://www.flightradar24.com/data/flights/ew9203 it landed at 12:13 local time on 18.01.2018, runway 23L or 23R.

the METARs for that timeframe say (emphasis mine)

201801181050 METAR EDDL 181050Z 27045KT 9999 SCT037 BKN043 08/00 Q0993 TEMPO 27045G55KT=
  201801181120 METAR EDDL 181120Z 27034G48KT 9999 -RA SCT028 BKN038 07/01 Q0995 TEMPO 27045G55KT=

So we have the average wind slightly decreasing from 45 to 34 kts in that timeframe (remember that METARS are in UTC), while the gusts slightly increase the worst case scenario from 45 to 48 kts.
Now, the pilots would not have had the second METAR, released minutes after they landed, and based on the information of the first METAR, we have:

45 kts of wind along the 270° direction
the 23R/L runways have an actual heading of 233°

this gives $45 \cdot \sin(37°)$ that results in slightly more than 27 kts of sidewind, less than the crosswind limit of 32 you mention.
Even in the worst case scenario, using round numbers, $45 \cdot \sin(40°)$ leads to 29 kts of sidewind, still below the limit.

I am also a pilot (single engine land, instrument) and while I've done some pretty heinous crosswind landings myself, I've always been near the CG of my aircraft. The first thing I noticed in that video was the speed at which the rear of the fuselage was moving at times - I suspect that even with all passengers buckled, there were some minor injuries in the cabin.
That said, I am with the other pilots in this thread - we were not in the cockpit, we don't have the information that crew had, nor knowledge of any extenuating or mitigating circumstances so any judgements made here are pure conjecture.

authors: Vladimir F Героям слава


text:
How were military gliders positioned to their departure point?
Modern sailplanes are usually positioned to their departure field using a trailer.  How did military gliders get to their departure field?

Boxed in crates and assembled onsite.
http://www.fagenfighterswwiimuseum.org/aircraft/glider/glider.html

Unlike powered airplanes that could either be flown directly overseas or shipped to distant ports fully assembled on the decks of aircraft carriers, gliders had to be shipped unassembled in wooden crates. Just one CG-4A glider, for example, required five enormous wooden crates to be shipped overseas. And again, unlike powered aircraft, which were ready for combat almost immediately upon reaching their destinations, the relatively delicate gliders required several days to be gently unloaded from cargo ships, uncrated, and painstakingly reassembled before they were ready for their test flights. This time-consuming shipping procedure was to be a source of considerable grief for the Allies throughout the war.

That makes a lot of sense.  Did the crates fit in trucks?  I do not think Germany used ships to send gliders to assault Belgium.

I expect the Germans just towed/flew them from Germany.

Interesting.  The 'citation needed' numbers for the range of their glider towing aircraft suggest they could achieve that, even if the gliders were built in the wrong part of Germany.


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What would be the safest way to drop thousands of small, hard objects from a typical, high wing, GA airplane?
The subject pretty much states my question, now I will provide a bit of background.
A family member, who lived on the west coast of Florida Manasota Key, collected tens of thousands of fossilized sharks teeth between the mid-1940s and the late 1970s. I have now become involved in deciding what to do with these sharks teeth. Here is one of the multitude of pictures available showing samples of these types of sharks teeth:

The vast majority of this collection ranges in size between a dime and a quarter and likely has the same level of hardness.
If you've visited one of the beaches in this part of Florida in the last 25+ years, you probably know that finding these treasures is no longer as easy as it used to be.  When I was a kid (late 1970s), I could usually come up with 10+ teeth in about a 2 hours stretch.  However, by the time my kids were of the age where this would be of interest (early 2000s), we were lucky if we found one a day.
What I'd like to do is return these teeth to the area just off shore of this beach thus giving future searchers a better chance of "re-finding" them.
Let's assume for the purposes of this question that the airplane involved would be a Cessna 172S. What would be a good way of doing such a drop without harming the aircraft itself?
I assume just dropping them out the window risks blow back that could damage the aluminum fuselage or tail assembly.
A couple of notes:

This is NOT a question about the legality of dropping items from an airplane in the United States. I am well versed with 14 CFR § 91.15 - Dropping objects, which states:

No pilot in command of a civil aircraft may allow any object to be dropped from that aircraft in flight that creates a hazard to persons or property. However, this section does not prohibit the dropping of any object if reasonable precautions are taken to avoid injury or damage to persons or property.

I am not interested in a solution harmful to the environment. Thus dropping them in taped boxes or rolled up newspaper would not be warranted, because that would be littering.
I'm certainly aware that renting a boat and dropping them off the side would be an alternative. That said, for the purposes of this question, I am specifically asking how to achieve this using a Cessna 172 (or similar) high wing GA airplane.

Comments are not for extended discussion; this conversation has been moved to chat.

Funeral homes sell gum bags for ashes. They dissolve in the ocean, releasing the ashes. You could make satchels and drop them in bundles with the teeth wrapped in kelp.

I'm leaning toward this answer.  Have you actually done this?  Also, are the bags biodegradable/environmentally neutral?

@bclarkreston I think you’re going to struggle to find anyone who’s actually dropped fossilised sharks teeth out a Cessna 172 in cremation bags.

Ah...let me clarify my question.  I meant to ask if the person answering the question had actually used gum bags to drop anything from an airplane ;-)

Needn't be special gum bags. They could be vitrified in anything biodegradable.  What comes to mind is "ice".

@Harper ice sounds like a perfect answer

Randy Dew, still hoping you will elaborate on your answer.  Have you ever used one of these gum bags to drop objects from an airplane?

Spitballing an idea... Not sure of the legality or practicality of this, but it's an idea that came to mind.
Using a piece of 2-3" diameter PVC pipe (sized as necessary to clear the largest tooth), attach (very securely - using the appropriate PVC glue and, possibly adding some screws) it to one edge of a sturdy (heavy plastic) box. Add some eye bolts to the sides of the box.
When you reach the drop zone, attach ropes (with swivel connectors, like on a dog's leash) to the eye bolts, slide the pipe out the window/door so that it hangs into the air stream, but below the empennage, slowly pour the teeth into the other end of the box and let them slide down to the spout and out of the plane.
The pipe will guide them down far enough to clear the bottom of the plane and give you controlled output. The ropes (attached to something inside the plane prior to take off) will ensure the box doesn't go sailing out of the plane.

Great idea but I'm not sure a pipe that would fit in plane would be long enough to ensure that flat objects like that might not generate enough lift to fly up and hit tail-

That's a valid thought I hadn't considered. It might be possible to heat the tube (I'm thinking a propane torch) then flatten the end so that the teeth come out vertically. That, of course, leads to the possibility of the teeth jamming inside the tube instead of slipping down smoothly.

A nonprofit in Kenya is doing something remarkably similar (link shows the distribution of pellets formed of tree seeds and fertiliser to degraded areas to encourage reforestation).
One short observation from the video suggests that the vacuum effect on the end of a flexible pipe hung out of the window of a light aircraft is sufficient to draw small objects from inside the cabin. Shark teeth might be too dense but it's worth a try.

Wow...that is similar!  The only difference might be that if these are seed pods they are likely quite a bit softer than sharks teeth would be.

What is the airspeed velocity of an unladen shark's tooth?

@Harper   African or European?

@MichaelRichardson African, obviously, that's where Kenya is located. ;)

Rig a curved PVC tube running from window to behind and below tail and have passenger pour teeth through a big funnel.  You may need a fairly large diameter pipe because with this version of pipe idea, the slope of the pipe is small, making it easier for teeth to jam.  Maybe the end of the pipe will even drag on ground during taxi and takeoff run or at least when you rotate for takeoff, which should be ok as long as the pipe has some flex, as the pipe doesn't have to survive multiple uses.  Check what pipe does when you put the aircraft tail tiedown ring on the ground before actually flying with this idea.  Also check what happens when you turn while taxiing.  Operating from a grass strip would help.
Calculate CG carefully!
Maybe even bring a pressurizable (pump-up) container of water to blast teeth out if get stuck, or something like a toilet snake, or just do sufficient tests on ground ensure won't get stuck.  You may want to drop teeth in steep climb to make pipe steeper.

Decided to make pipe idea a separate answer

You can crack the door on a Cessna 150 or 172 while in flight, probably can most other high wing aircraft. So just crack the door, put a PVC pipe out the door far enough so it is out in the slipstream, and pour your shark's teeth into the pipe. Further away from the tail and easier to manipulate than out the window.

Oh an keep your seatbelt on if you're going to open the door. You're welcome

You can steer a Cessna by opening and closing the doors alternately. Demonstrated to me by my instructor many decades ago.

I think the concern is the flat shape of teeth may make them follow very unpredictable trajectories including climbing upward so it might take a very long pipe to do that- as noted in other similar comment to other similar idea.

@MikeY you can steer an old VW Beetle by alternately opening its "quarter glass" (front vent) windows.  Demonstrated to one of my aero profs about the same time as what you saw.

@Camille, you're going to have to post video of that, or doubts are not rendered asunder. :)

@MikeY this may have been even before the first movie camera in a car ("Bullitt"?), but I'll attempt a video reconstruction myself if nobody here beats me to it.

The common technique for scattering ashes is to put them in a small cloth bag, under the wing and well away from the fuselage.   Tie the bag with a slipknot, and open it by tugging on the other end of a rope run under the wing to a cockpit window.
You can further avoid risk to the airplane body by paying careful attention to the prevailing wind, and making sure the drop happens on the leeward side of the plane while crabbing.  This should make the pieces move away from the plane very quickly as soon as the bag is opened.

I think they might fly up and hit wing.  Maybe cover wing behind bag with adhesive film of some kind to protect paint.

Wait, are you suggesting that the prevailing wind direction makes any difference?  You said "crabbing", did you really mean a simple "crab" like we do all the time on a cross-country flight, and during a non-slipping style of crosswind landing up the point where we "kick out the crab", or did you mean a true cross-controlled slip to put a sideways flow over the aircraft, in which case the meteorological wind direction would be completely irrelevant? Sorry, but I have no choice but to downvote until clarified!

@quietflyer seems pretty clear to me what he is saying, aren't crabbing and slipping two different maneuvers?  The point of crabbing in his answer is that you want the wind to be moving perpendicular to the fuselage so that the objects are more likely to blow leeward.

@bclarkreston - that is not crabbing. It is a some form of a slip, or possibly a wings-level skidding turn which arguably ought to fall within the larger aerodynamic category of sideslip, i.e. sideways flow.  Anyway what you are describing is definitely not crabbing.  Could be the basis of anothet ASE question - "what is crabbing, in the aviation context, and does a yaw string (located outside of any propwash) blow straight or sideways?"

@quietflyer downvoting based on a small thing like that when the general idea is sound, seems quite petty to me, especially when you have several heavily downvoted answers.

@Notts90 - it is a very fundamental point.  It is much more important that this forum does not sow confusion about the basic physics of flight, than that someone gets the best answer on how to throw sharks teeth out of an airplane.

Plus it is easy enough to fix the answer.

Out the window should work fine, assuming they're as dense as a typical fossil. The "blowback" hazard is with low-density or fine particulate materials such as the human ashes that you hear all the horror stories about.
You can fly at a lower airspeed to further improve the clearance from the empennage.

It sounds like you're concerned that the teeth would fly around uncontrollably after being released and possibly damage the aircraft.  Try changing their aerodynamic properties.  The answer that mentioned marbles got me thinking that if you rolled the shark's teeth in cookie dough then the teeth would fall through the air in a more predictable fashion.  I like the idea of a little ball of biodegradable cookie dough, with a crunchy shark's tooth center, falling through the sky.  Then those ideas about using a pipe or just tossing out the window would be more viable.  (Rolling the dough balls in powdered sugar to facilitate sliding down a pipe is optional.)

10000 teeth times a teaspoon of dough each is already 50kg of cookie dough.

@DavidRicherby. So that's a yes? :)

Oh, sure,  ... and then all sorts of creatures, including children, will try to eat the cookie dough!

I think you're just looking for an excuse to eat all the extra cookie dough :)

If they were marbles of the same weight, I think you could be sure would not hit tail if just poured out window, but maybe not with those teeth.  Here's one solution: remove brace from side window to permit full opening. Put teeth in bag.  (Optional: fill extra space in bag with sand to make heavier).  Have top of bag tied shut with flaps that will open when a string pulls out a pin.  Have bottom of bag securely tied to strong long rope.  Throw bag out window, string  comes tight first, opens top of bag, then rope comes tight and holds bag securely upside down.  Or just do it with one rope, you just have a loose "bight" threaded through the rubber band that holds the bag closed, as is done with parachute shroud lines.  (You could even buy a hang glider parachute deployment bag.)
Anyway after deployment the empty bag trails harmlessly way behind the tail till landing.
Better yet remove door and push bag out door.  How big a bag would it take to contain all the teeth anyway?
Simpler- a strong-ish plastic bag like a trash compactor bag or heavy garbage bag.  Remove door and passenger seat to accomodate huge bag with thousands of teeth.  Bag is filled with teeth, bunched up on top, wrapped round with twine, then a long heavy rope is tightly tied around "bunched" point.  Leave lots of excess bag material on top above "bunch" point so bag cannot slip out through twine and rope.  Bag is tied to secure strong fuselage member or landing gear.  To drop, do an extreme slip, or push bag out with broom or similar.  Bag falls to end of rope, bottom rips open, teeth fall, empty bag trails well behind tail.  (You'll use a rather long rope.)
Do tests on ground out of second-story window with same kind of bag to make sure it will consistently rip open when reaches end of rope and doesn't pull loose through rope and twine.  Maybe using a bag full of same weight of gravel or sand, so you don't have to pick up all the teeth again.  Of course the teeth will do a better job of ripping the bag than gravel or sand will.  Make sure the bag is strong enough that the teeth won't rip the bag in the plane, and be sure the plane has an interior such that loose objects can't migrate to tailcone.  Tie bag securely into place before takeoff with rope or strap that you can easily undo.  Maybe better to leave passenger seat in place after all to facilitate buckling bag into place; also it will put bag in better postion for you to shove it out the missing door with one hand and avoid issue with bag clearing door sill.  Make sure the bag cannot interfere with controls in any way!
A bag with a ripstop kind of "weave" (texture) would help stop minor tears and punctures  from propagating before the drop, if such a thing exists in a disposable bag.  You may end up needing to double-bag the teeth- do some experimenting.

I see another answer had similar idea, but I would rig a long curved pipe basically parallelling fuselage before takeoff.

I've seen a number of questions asking about attaching a GoPro type camera to the outside of a plane. The general consensus is that is a "modification" requiring approval and paperwork. I would think attaching a pipe prior to flight would fall into that category as well. Who knows, maybe my "temporary pipe out the window" suggestion would cause CAA trouble, too.

Well, good point, but maybe he can operate from a secluded airstrip where no one will care.  Sure never stopped me from attaching Go Pros!

I'm not sure recommending "skirt the law and risk a potential FAA violation" is something we want to be seen doing at ASE... If OP chooses to ignore warnings and do it anyway, that's on him. (Again, don't know if that's legal or not.)

(comments were intended for pipe answer which is now a separate answer)

The question "How big a bag would it take to contain all the teeth anyway?" is valid.  Let me give that some thought...will add the original post.

Inspired by another answer What would be the safest way to drop thousands of small, hard objects from a typical, high wing, GA airplane? (and now I also notice the comment suggesting to freeze the teeth in ice) :  make a giant shark's tooth cookie!   Mix dough and teeth together in barrel, let harden, cut away barrel, and take mister sharktoothcookie for a one-way flight in a plane with door removed.


text:
How to calculate the best climb rate and glide rate?
Considering the lift equation
$$L = C_L \frac{1}{2}\rho v^2 s$$
Given $P$ is 1,000 ft, $\rho$ is 0.002308, and $V$ is the cruise speed of a Piper Archer or 126 knots, we get
$$L = (0.4) (0.002308) (\frac{1}{2}) (126)^2 (160)$$
or 1,172.5 Newtons.
What are the pencil-and-paper formulae for calculating the best-climb and best-glide rates?

Without a complex aerodynamic model, I'm not sure it can be calculated.  Just read the POH for this info?

Are you asking about the airspeed that provides the best climb rate and glide rate, or are you asking for a way to calculate the actual vertical feet per minute, or feet per mile?

What's the actual problem you're trying to solve? Are you curious about how the figures in the POH are calculated? Are you a student pilot wanting to know how to get this information from the table in your POH?

Does this answer your question?

Did you ever consider to look at the units in your calculation?
You can't just throw together some numbers and expect a correct result. Start by converting all input to the much more sane SI units and see how it goes from there. If you plug in the units instead of the numbers on the right side of the equation, you can check for correctness by comparing to the intended unit on the left side.
Hint: 1 Newton = 1 kg·m/s².

So they can be converted all in the same SI units? even the surface area?

@AishveTorah: In the proper SI units, yes. Surface area in m², density in kg/m³ and so on.